In this paper, a new algorithm HCOUNT + is proposed to find frequent items over data stream based on the HCOUNT algorithm. The new algorithm adopts aided measures to improve the precision of HCOUNT greatly. In additi...In this paper, a new algorithm HCOUNT + is proposed to find frequent items over data stream based on the HCOUNT algorithm. The new algorithm adopts aided measures to improve the precision of HCOUNT greatly. In addition,HCOUNT + is introduced to time critical applications and a novel sliding windows-based algorithm SL-HCOUNT + is proposed to mine the most frequent items occurring recently.This algorithm uses limited memory (nB · (1 +α) · e/ε·In(-M/lnρ)(α〈1) counters), requires constant processing time per packet (only (1+α) · ln(-M/lnρ(α〈1)) counters are updated), makes only one pass over the streaming data,and is shown to work well in the experimental results.展开更多
文摘In this paper, a new algorithm HCOUNT + is proposed to find frequent items over data stream based on the HCOUNT algorithm. The new algorithm adopts aided measures to improve the precision of HCOUNT greatly. In addition,HCOUNT + is introduced to time critical applications and a novel sliding windows-based algorithm SL-HCOUNT + is proposed to mine the most frequent items occurring recently.This algorithm uses limited memory (nB · (1 +α) · e/ε·In(-M/lnρ)(α〈1) counters), requires constant processing time per packet (only (1+α) · ln(-M/lnρ(α〈1)) counters are updated), makes only one pass over the streaming data,and is shown to work well in the experimental results.